Recently, in the field of coatings and adhesives, organic solvent-based systems are being replaced with water-soluble or dispersible systems as an anti-pollution measure or resource saving.
However, the conventional water-based coatings have disadvantages in that, since they have no crosslinkable functional group in the molecules, they are subject to the strong influence of surfactants used in the polymerization, which remarkably deteriorate the weatherability, water resistance and stain resistance of formed coating films, resulting in inferior film performances as compared with solvent-based paints.
Therefore, to provide crosslinkable functional groups in the molecules, an application of an alkoxysilyl group-containing emulsion to the field of coatings has been proposed. However, the alkoxysilyl group is easily hydrolyzed in the presence of water so that the film-forming performance of the emulsion is deteriorated considerably after aging and, moreover, the emulsion is poor in mechanical stability and white enamel gloss.